My Baby's Soft Spot Looks Bulging
The short answer
A bulging fontanelle can be a sign of increased pressure inside the skull and needs immediate medical attention, especially if your baby also has a fever, vomiting, or seems very unwell. However, brief bulging during crying or straining is normal. The key is whether it stays bulging when your baby is calm and upright.
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By Age
What to expect by age
0-3 months
In newborns, the fontanelle should feel soft and flat when your baby is calm and upright. It's normal to see gentle pulsing and slight fullness when crying. However, if the fontanelle remains bulging or tense when your baby is calm, or if your baby has a fever, poor feeding, or unusual sleepiness, seek immediate medical care as this could indicate meningitis or another serious infection.
3-6 months
You may notice the fontanelle tenses and bulges briefly when your baby cries, coughs, or has a bowel movement - this is completely normal. What matters is the appearance when calm and upright. A persistently bulging fontanelle, especially with other symptoms like high fever, irritability, or lethargy, requires urgent evaluation.
6-12 months
As your baby becomes more active, you might see the fontanelle react to exertion or crying. This is normal. A bulging soft spot to worry about is one that stays full and tense even when your baby is calm, quiet, and sitting upright. If accompanied by vomiting, fever, seizures, or a stiff neck, go to the emergency department immediately.
12-18 months
The fontanelle is smaller now but should still not bulge when your toddler is calm. Conditions like shunt malfunction (in children with hydrocephalus), severe head injury, or infections can cause a bulging fontanelle. If you notice persistent bulging, especially after a fall or with illness, seek urgent medical attention.
18 months+
Most children's fontanelles close between 18 and 24 months. Once closed, this sign is no longer useful. If your toddler's fontanelle is still open and appears bulging along with symptoms like severe headache, vomiting, or altered consciousness, go to the emergency department.
What Should You Do?
When to take action
- The fontanelle bulges or tenses only when your baby is crying, coughing, or straining
- The soft spot returns to flat and soft immediately when your baby is calm
- You can see gentle pulsing in the fontanelle in rhythm with your baby's heartbeat
- Your baby is otherwise well, feeding normally, and acting like themselves
- You're unsure whether the fontanelle is truly bulging or just normal pulsing
- Your baby's fontanelle seems slightly fuller than usual but your baby is completely well
- You want your pediatrician to check the fontanelle at the next well visit to give you a baseline
- The fontanelle remains bulging and tense when your baby is calm and upright
- Your baby has a bulging fontanelle along with fever, vomiting, seizure, or extreme irritability
- Your baby seems very unwell, is difficult to wake, has a weak cry, or has a stiff neck
- Your baby had a significant head injury and now has a bulging fontanelle
Sources
Related Resources
Trust your instincts. If something feels wrong, reach out to your pediatrician.
Worrying about your baby means you care. That is a good thing.
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